Limit script access on Chrome

This change limits the script's access to *.reddit.com on Chrome.

Chrome has it's own built-in Greasemonkey script. It appears to ignore @include, but respects @match. Additionally, Chrome doesn't appear allow http*:// syntax; it requires that you explicitly use http:// and https:// if you want to provide both.

Without this change, the script runs on "all domains" in Chrome.